Stabilizer for firearms



July 3, 1956 L.. F. LANDWEHR STABILIZER FOR FIREARMS Filed Jan. 25. 1953 R. m E V w.

Louls LANDWEHR BY M v United States arent Fatented July 3, 1956 lice This invention pertains to stabilizers such as are used on rifles in the practice known as bench shooting in which the rille is supported on a according to ytheir placement upon the target.

One of the objects of this invention is to provide a stabilizer having supports for the rifle barrel, which may be adjusted to engage the barrel ywith any desired pressure.

Another object is to provide such a device with an indicator whereby the amount of such pressure may be noted.

Another object is to provide means for equalizing the pressure on a plurality of supports engaging the barrel, and to make `such equalization automatic.

Further objects will appear in fthe following description taken in connection with the accompanying drawing, showing a preferred embodiment of this invention, in which- Y `Figure 1 is a side view of a rie equipped with a stabilizer embodying this invention; i

Figure 2 is an enlarged plan view of the stabilizer mounting;

, Figure 3 is an enlarged section on line 3-3 -of Figure l;

Figure 4 is a detailed section somewhat enlarged on line 4 4 of Figure l3 and j Figure 5 is a view similar to Figure 3, illustrating another embodiment of this invention.

Fig. 6 is a view similar to Fig. 5 showing another embodiment of the invention.

Referring now to the drawing, 5 designates the riile barrel, and 6 the stock which supports it. These may be of any usual construction, ordinarily of the `type used for bench shooting. In accordance with the preferred embodiment illustrated in Figures 2 to 4, the stabilizer comprises a lbase 7 lwhich may beset into a suitable recess in the forward end of the stock 6. rIhe base 7 may be constructed of any suitable metal. Aluminum has been Ifound very satisfactory. The base 7 is formed with a plurality of cylinders 8 adapted to contain hydraulic fluid. As shown in Figure 3, these cylinders are positioned so that their axes intersect substantially in the center line of the bore of the barrel 5. The angle between these axes is usually about 120, although this may vary. Movably mounted in the cylinders B are pistons 9. These may be equipped with packing rings 10.

The pistons 9 may be arranged to abut directly against the `barrel S, the piston heads providing -abutments for supporting and stabilizing the barrel. However, it has been found advantageous to provide separate abutments 11 between the pistons and the barrel. These abutments are preferably constructed of a slightly yieldable material such as nylon which is not permanently deformed by the shock of discharge of the rie but is yet substantially rigid for support of the barrel.

In order to equalize the hydraulic pressure in the two cylinders 8, a passage 12 is formed in the base 7 connecting said cylinders. A third cylinder 13 is formed in the base 7 so as to connect with the cylinder 8 by a passage 2 12'. A piston 1'4 in this cylinder is arranged to be moved by a thumb screw 15 so that by movement of the piston 8 and the passage 12 with hydraullc fluid. Thisjduct may be closed by a screw plug 18.

a With the structure so far described, the barrel 5 which stock 6 is additionally supported at an intermediate point of its length by the p1`shydraulic fluid 9, while their pressure on the barrel is maintained constant and equal. Since the hydraulic iluid is substantially non-compressible, it provides a rigid support to receive the shock of the discharge of the rifle. Furthermore, if such shock should be delivered unequally to lthe two shock of the explosion.

As some bench shooters may desire to support the barrel 5 at more than two points so as to prevent shifting 'in any direction, the embodiment of Figure 4 provides for such support. In this case, the base 20 is provided with extensions 21 22 provided with abutments 23 engaging the barrel 5 above its horizontal center line. The base 20 is also provided with cylinders 24 in which pistons 25 are movably mounted and provided with abutments 26 engaging the barrel 5. The cross passage 27 the piston 29 may be moved to adjust the pressure in the pas-sage 27 and the cylinders 24.

In the embodiment of Figure 4, one or more valves 31 may be provided in the passage 27 so as to cont-rol the ilow of lfluid between Ithe cylinders 24. These valves may or may not be used as desired. They may be adjusted by means `of screws 32 `to a more or less completely closed position, form-ing thereby a restriction in the passage 27 to control the 4rate of ow of the hydraulic fluid through said passage. These valves may be used in two ways.

permit readjustment of the pressure. Alternatively, they may be left open and one or both `of them adjusted to provide a restriction in the passage of ow.

It will be` clearly noted `that. if desired, the screws 22 may be replaced by hydraulic pistons such as 2S by suitable modifications of the base2i. Connecting passages, suchtas`27, may belprovided-to'equalize thefpressure in' allcylinders,.and`valves,isuch as 31,may: be placed at' such points asto restrictI or'feut 'olif the owof such fluid1 where desi-red: For example,-the base 20 might1be pro'- vided; in place of the upward extensions ofthe members 21,. with" an upper half substantially identical' with the lower half;asillustratedy in Fig; 5; therebyprovidingA a pair Vol pistons2`5finarelation to'thebarrel 'similar tothat of the screws' 22: Such'a' modification `isfillustra-ted in Fig. 6 wherein afbase' section Ztysimilar" to thebase Z0; is superimposed thereon. t

It willibe-see'n 'that this invention provideswal simple'fand efiectivefmeans-forstabilizinga rifle' barrel'of the type hereinvolVed.- The supporting-abutments maybe locatedl asdesi-red around thev circumferenceof -thc barrel, and connectedA by 'uid passages so that y'the supporting f pressurein'all'the` cylinders maybe equalized. Thus an equal pressure on'all snpportsm'ay-'ber had. Furthermore', un equal pressure in any desiredratio may'bchadby'varying: the size-of the pistonsgisuch ratio being maintained constantatall pressures of` the fin'id.y Theuidpressurc is adjustable to any desired value, and such value is indi-vv cated onthe' gauge 16.- Thisenable's Ithe operatorI tol knowexactly what pressure is used, and to ke'ep a=record ofit for comparisonwith pa'st or future operations.-

Thebase'l, insteadof being4 set into a recess-of the stock asshown, maybe attached at the endof the stock.

This' avoids the necessity lof recessin'gfthestockiandrnakcs' it easier to apply different stabilizers interchangeably;

Variouschanges may be made inthe details of construction, within the scope of the appended claims, without 'departingfrom'the spiritofthis invention. Parts of` thef invention may be used without the-whole and immovements-may be added' while' retaining someL or all of the advantages of the-invention.

I claim-z l; Astabilizer for a firearmy 'having a barrel and a sup' port thereforsuch Ias `a stock; comprising, al'base mountedy in said support, said base having a plurality-ofhydraulic cylinders; pistonsmovable in-:said cylinders; abutments supported by'saidpistons and-in supporting engagement?-A with'said barrel,r said base' having 'a passagel for hydraulic fluidvconnecting-'said cyli11ders,-and-`mcans Vforcontrollingy the hydraulic pressure in saidpassage.

2. Asstabilizeri for a firearm-having a barrel anda supportvtherefor` such'as a stock; comprising; a'base mountedin said support, said ybase havingfa pluralityof hydraulic-cylinders, pistons movablev in" said` cylinders;

abutments lsupported-'by said pistons andin supporting engagement with said barrel, said ibase' having! a passage forv hydraulic-'fluid connecting said cylinders, and -means formingfa restriction in said-'passage'adapted 'tov control theiflowof fluid therein.

3. lA stabilizer for a firearmv having a barrel and asuplil port therefor such as a stock, comprising, a base mounted in said support, said base having a plurality of hydraulic cylinders, pistons movable in said cylinders, abutments supported by said pistons and in supporting engagement with said barrel, said base having a passage for hydraulic fluid connecting said cylinders, and a valve in said passage adjustable to control the-f`iowot tluid therein.

4. A stabilizer for a firearm having a barrel and a support theref'rAll s'u'cli asvf a 'stocky cdr'xprising` a plurality o'r stabilizing-means carried by saidsupport and including abutments engaging's'aid barrel ata plurli'tyo'i points, each of said meanslbeing responsive'to'hydiaulic pressure, a conduit carryinga liquid connecting said means whereby pressure e'iertedy on' sa'i'dl stabilizing means is equal, and means for controlling the pressure in said conduit.

5. A stabilizer for a firearm having a barrel and a s upport f therefor such as l af stock, i ccin'rp'isingf1 a plurality/'oi stabilizing means' carreu' by saidIl Suppen* and-'5 including abutmen'tsA engaging" saidfbarrelj at a plurality' of I points;

equa1`,faa manual-ty operabt valve" in said-2 co'ndui't, A and means for controllingltb'e pressure'insaidconduit.'

ofhydraulic'lv cylinders'r carried-f b'y5 said i' support,l Y pistons 5 movableinsaid cylir"1de'rs',`L abturn'ents" supporte'wby said piston in said otherycylinder.

port therefor such as a stocll,"'comprising'abpluralityofI hydraulic'cylinders carried'b'y said`support; pi'stons'imo able in said cylinders, abutments supported by saidpist sure exerted on said pistons is edualg'aiiiitlir'cylinderZ connected 'tol said 'conduit'g" a pistoniin'said fotherfcy'lirideii, 

